Cold weather drove hundreds of manatees to seek sanctuary this weekend in the warm-water discharge zones of South Florida power plants.
An aerial survey Monday in Broward County found 304 manatees, the vast majority herding into the cooling lakes of the power plant west of Fort Lauderdale-Hollywood International Airport and east of State Road 7.
No aerial survey took place in Palm Beach County, but officials had expected the cold to bring an influx to the power plant at Riviera Beach, where Florida Power & Light is required to discharge warm water when the temperature drops to a certain point, even though the plant has been taken out of operation to be modernized.
Extremely sensitive to cold, manatees learned decades ago that power plants could provide warm water refuges to replace the warm springs that were once abundant around the Florida peninsula. The plants suck in cold water to cool their turbines and discharge at a higher temperature.
"There used to be a lot more warm-water refuges," said Pat Quinn, Broward County's manatee coordinator. "Because we're sucking so much water from underground for human use, there's not as much water flowing out of the springs as there used to be. There used to be warm-water springs down here, and as they become less and less, the manatees started coming to the power plants."
About 270 manatees were counted Monday at the power plant near State Road 7.
Any area that draws lots of manatees will quickly get stripped of seagrass and other food. So when the weather warms up – something the manatees sense as they come up for air – they generally head quickly to sources of nourishment. The nearest big beds of seagrass are in the Lake Worth Lagoon.